Organic peroxides, their preparation and their applications

ABSTRACT

where X is a bivalent radical such as alkylene; R1 is hydrogen or an organic radical; R2 is alkylene alkoxy carbonyl; and R3 is an organic radical. Method of preparing tetraperoxides by addition reaction between a bis-hydroperoxide and a carbonyl compound to form a dihydroxy diperoxide, followed by condensation of the dihydroxy diperoxide with a tertiary monohydroxide. The tetraperoxides are useful for vulcanizing saturated elastomers, crosslinking plastomers, and initiating radical polymerization.   Tetraperoxides of the formula

United States Patent 1191 Sacrini et al.

ORGANIC PEROXIDES, THEIR PREPARATION AND THEIR APPLICATIONS Inventors: Egeo Sacrini; Claudio Cavallotti,

both of Milan, Italy Assignee: The B.F. Goodrich Company,

Akron, Ohio Filed: Apr. 23, 1975 Appl. No.: 570,600

Related US. Application um Division of Ser. No. 373,934, June 27, 1973, which is a division of Ser. No. 62,128, Aug. 7, 1970, Pat. No. 3,775,465.

Foreign Application Priority Data Dec. 23, 1975 3,419,577 12/1968 'Breckert et al. 260/610 R Primary Exaniiner.James 0. Thomas, Jr. Assistant Examiner-W. B. Lone Attorney, Agent, or Firm-Hubbell, Cohen, & Stiefel [57 A ABSTRACT Tetraperoxides of the formula where X is a bivalent radical such as alkylene; R is hydrogen or an organic radical; R is alkylene alkoxy carbonyl; and is an organic radical. Method of preparing tetraperoxides by addition reaction ,between a bis-hydroperoxide and a carbonyl compound to form a dihydroxy diperoxide, followed by condensation of the dihydroxy dipe'roxicle with a tertiary monohydroxide.

The tetraperoxidesiare useful for vulcanizing saturated elastomers, crosslinking plastomers, and initiating radical polymerization.

7 "1 Claim, No Drawings BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a new series of ,organic peroxides'More particularly, it relates to a process for the preparation of peroxides havingifour peroxidic functions, to novel peroxides having four-peroxidic functions, and to the use of such peroxides as radical polymerization initiators, vulcanizing agents for elastomers, crosslinking agents for plastomers, and as organic reactants. t r t 2. Description of the Prior Art It is well known that organic compounds of a peroxidic nature are important as generators of free radicals and consequently as initiators of free radical polymerizations, as crosslinking agents for plastomers and as vulcanizing agents for elastomers.

THE INVENTION The present invention provides a particular type of new organic peroxides having good stability and low volatility at temperatures higher than room temperature, such peroxides being particularly suitable both as vulcanizers for elastomers and as -crosslinking agents for plastomers.

The present invention provides a new series of organic peroxides characterized by the presence of four peroxidic groups, these peroxides being defined by the general formula:

wherein; Y 1 v each of R may be hydrogen, alkyl, haloalkyl, cycloalkyl, halocycloalkyl, alkylcycloalkyl, said .groups vhaving 1-15 C, aryl, haloaryl, alkaryl, said groups having 6-15 C, oxyalkyl, oxyalkylaryl, or oxycycloalkyl, said groups having 1-l5 C; each of R may be alkylene alkoxy carbonyl wherein alkylene group has 1-4 C and alkoxy grouphas 1 to 4 C such as methylene ethoxy carbonyl,

CmcrnOH-Cm or the like; 1 each of R may be alkyl, haloalkyl,.-said groups having 4-12 C, cycloalkyl, halocycloalkyl, alkylcycloalkyl, said groups having 4-21 C, aryl, alkaryl, haloaryl, said groups having 6-24 C, oxyalkyl, oxyalkylaryl, oxycycloalkyl, said groups having 4-24 C, or acyl, having 6-12- C; preferredlradicals .being tertiary alkyl such as tert.-'butyl, tert.-amyl, and cumyl; and X is alkylene, haloalkylene, arylalkylene, said groups having 2-18 C,,alkenylene halo-alkenylene, arylalkenylene, said groups having 2-18 alkinylene,

5i Examples of compounds within the above cited genhaloalkinylene, aryl alkinylene, said: groups having 2-18 C, oxyalkylene, having 2-1 2 C, arylene, alkyl arylene, or halo arylene, said groups having 6-18 C eral formula include:

1) a-a' .[2-tert. -butyl peroxy-(3-ethoxycarbonyl)-isoprOpyIidene-Z peroxy] 1,3 diisopropylbenzene,

2 a-a' [2-tertebutyl'-peroxy-(3-ethoxycarbonyl)-isopropylidene-2 peroxy] 1,4 diisopropylbenzene,

3)" 0H1 [2-cumyl 'peroxy-(3-ethoxycarbonyl)-isopropylidene-2 peroxy] 1,3 diisopropylbenzene,

4) 01-11 [Z-cumyl pe'roxy-(3-ethoxycarbonyl)-isopropylidene-2 peroxy] 1,4 diisopropylbenzene.

The peroxides of this invention show the unusual properties of being endowed with a good stability and a low volatility at temperatures higher than room temperature. These properties permit the=compounds to be phenomena.

This invention provides, moreover, a process for the preparation of the foregoing peroxides, as well as of other known tetraperoxides, e.g., those disclosed in US. Pat. No. 3,489,730 at column 1, lines 41-59, the contents of which are incorporated herein by reference, 'throughtwo successive steps. In'the first step there occurs an addition reaction between a bishyd'roperoxide and'a carbonyl compound, with the formation of a diperoxide' having a double hydroxy function. In'the second step'there occurs a condensation reaction between the previously obtained diperox- 1 ide and a mono-hydroxide of the tertiary type.

According to a preferred embodiment, the desired tetraperoxides are prepared in the presence-of a suitable solvent by reacting in the first step (1) an organic carbonyl compound of the formula: R,CO R

wherein each of R and R may be hydrogen, alkyl,

haloalkyl, cycloalkyl, halocycloallcyl, alkylcycloalkyl,

said groups having l-l5 C, aryl radicals, haloaryl, alka- "ryl, said groups having 6-15 C,oxyalkyl-, oxyalkylaryl-,

oxycycloalkyl, said groups having1-1'5 C; R, may also be an alkyl ene alkoxy carbonyl wherein ,alkylene has 1 to 4G and alcoxy has 1 to 4 C;'or R and R together with the central carbon atom from a cycloaliphatic ring, having 4 -1 6 C, which ring maybe alkyl-, halogen- Examples of compounds embraced by the above formula include:

h) a-a (1-hydroxy-cyclohexylidene-l-peroxy) 1,3

diisopropylbenzene;

i) a-a' (l-hydroxy-cyclohexylidene-1-peroxy) 1,4

diisopropylbenzene;

j) a-a 1-hydroxy-4-tert.-butyl-cyclohexylidene-1- peroxy) 1,3 diisopropylbenzene;

k) a-a (1-hydroxy-4-tert.-butyl-cyclohexylidene-1- peroxy) 1,4 diisopropylbenzene;

l) a-a' (l-hydroxy-cyclododecylidene-l-peroxy) 1,3

, diisopropylbenzene;

m) a-a' (1-hydroxy-cyclododecylidene-1-peroxy) 1,4

diisopropylbenzene;

n) a-a' (2-hydroxy-n-butyliden-2-peroxy) 1,3 diisopro pylbenzene;

) 01-01 (4-hydroxy-2,6,8 trimethyl nonylidene-4- peroxy) 1,3 diisopropylbenezene; p) 01-11 [2-hydroxy-(3 phenyl)-propylidene-2-peroxy] 1,3 diisopropylbenzene.

The peroxides defined by the foregoing formula are new Compounds, and are useful as initiators of radical polymerizations.

The diperoxides obtained as described above are then reacted in the second step of the process, with mono-hydroperoxides in the presence of suitable dehydrating agents and catalysts of an acid nature at a temperature between about 30 and +80C, preferably between about and +50C.

Examples of bis-hydroperoxides which are suitable for use in the first step of the process include: diisopropylbenzene-l,3-dihydroperoxide; diisopropylbenzene- 1,4-dihydroperoxide; 2,5-dimethyl-2,S-dihydroperoxyhexane; 2,5-dimethyl-2,5-dihydroperoxide-hexene-3; 2,5-dimethyl-2,5-dihydroperoxy-hexyne-3; etc.

Examples of carbonyl compounds suitable for use in the first step of the process include; aliphatic ketones such as methyl ethyl ketone, acetone; substituted aliphatic ketones such as ethyl-acetacetate; cycle-ketones such as cyclopentanone, cyclohexanone and cyclododecanone; cyclo-alkyl-ketones such as 4-terbutyl cyclohexanone; alkylarylaldehydes such as cinnamaldehyde; alkylheterocyclic aldehydes such as furyl acrylic aldehyde.

The mono-hydroperoxides which may be used in the second step of the process are of the type: R, OOH wherein R has the above defined meaning, preferably wherein a tertiary carbon atom is bound to the hydroperoxide group. Examples of such mono-hydroperoxides include: tert.-butyl hydroperoxide and substituted tert.-butyl hydroperoxides, cumyl hydroperoxide and substituted cumyl hydroperoxides, methyl-cyclohexyl hydroperoxide, 2-methy1-2 hydroperoxide-butyn-3, methane 'hydroperoxide, etc.

Solvents suitable for use in this invention include linear aliphatic hydrocarbons having 6-10 C; linear aliphatic halogenated hydrocarbons having 1 or 2 C and 1 to 4 Cl; cycloalkphatic hydrocarbons having 6-10 C; aromatic hydrocarbons having 6-9 C, which may be halogenated with 1 or 2 Cl; ethers for instance, ethyl ether.

The molar ratio between the bis-hydroperoxide and the carbonyl compound used in the addition reaction should be between 1:12 and 1:10, and preferably between l:l.5 and 1:5. Catalysts of an acid nature may be of the HCl, H and HClO type.

For the second step of the process, wherein a condensation reaction take place, the molar ratio of diperoxide having a double hydroxy function to monohydroperoxide should be between 1:2 and 1:10, and preferably between 1:3 and 1:5.

As previously noted, the overall process of this invention can be employed to prepare a wide variety of tetraperoxides, many of which are known, many of which are new. Examples of tetraperoxides which can be made by the process of this invention include the following:

1) 01-01 (2-cumyl peroxy-isopropylidene-Z-peroxy) 1,3

diisopropylbenzene;

2) 01-01 (2-cumyl peroxy-isopropylidene-2-peroxy) 1,4

diisopropylbenzene;

3) 01-01 (2-tert.-butyl-peroxy-2-phenyl ethyl-2-idene-2- peroxy) 1,3 diisopropylbenzene;

4) 01-01 (2-tert.-butyl-peroxy-2-phenyl ethyl-2-idene-2- peroxy) 1,4 diisopropylbenzene;

5) 01-01 (2-cumyl peroxy-2-phenyl ethyl-2-idene-2- peroxy) 1,3 diisopropylbenzene;

6) 01-01 (2-cumyl peroxy-Z-phenyl ethyl-2-idene-2- peroxy) 1,4 diisopropylbenzene;

7) 11-01 [2-tert.-butyl peroxy-(3-ethoxycarbonyl) isopropylidene-Z-peroxy] 1,3 diisopropylbenzene;

8) 01-04 [2-tert.-butyl peroxy-(3-ethoxycarbonyl) isopropylidene-2-peroxy] 1,4 diisopropylbenzene;

9) a-u' [2-cumyl peroxy-(3-ethoxycarbonyl)-isopropylidene-2-peroxy] 1,3 diisopropylbenzene;

10,) oz-a' [2-cumyl peroxy(3-ethoxycarbonyl)-isopropylidene-2-peroxy] 1,4 diisopropylbenzene;

11') 11-01 (1-tert.-butyl peroxy-cyclopentylidene-lpe'roxy) 1,3 diisopropylbenzene;

1-2) 01-01 (l-tert.-butyl peroxy-cyclopentylidene-1- peroxy) 1,4 diisopropylbenzene;

13)"d-a (l-cumyl peroxy-cyclopentylidene-1-peroxy) 1,3-diisopropylbenzene;

14) 01-01 (l-cumyl peroxy-cyclopentylidene-l-peroxy) 1,4 diisopropylbenzene;

15) 01-01 (1-tert.-butyl peroxy-cyclohexylidene-1- peroxy) 1,3 diisopropylbenzene;

16) a-a' (1-tert.-butyl peroxy-cyclohexylidene-lperoxy) 1,4 diisopropylbenzene;

17) vai-oz' (l-cumyl peroxy-cyclohexylidene-1-peroxy) 1,3 diisopropylbenzene;

1'8) a-a' (l-cumyl peroxy-cyclohexylidene-l-peroxy) 1,4 diisopropylbenzene;

19) our (1-tert.-butyl peroxy-4 tert.-butyl-cyclohexylidene- 1 -peroxy) 1,3 diisopropylbenzene;

20) 01-04 1-tert.-butyl peroxy-4 tert.-butyl-cyclohexylidene-1-peroxy) 1,4 diisopropylbenzene;

21) a-a (1-tert.-butyl peroxy-cyclododecylidene-1- peroxy) 1,3 diisopropylbenzene;

22) 01-01 (1-tert.-butyl peroxy-cyclododecylidene-lperoxy) 1,4 diisopropylbenzene;

23) 01-04 (2-tert.-butyl peroxy-n-butylidene-Z-peroxy) 1,3 diisopropylbenzene;

24) an (4-tert.-butyl peroxy-2,6,8 trimethyl nonylidene-4-peroxy) 1,3 diisopropylbenzene;

25) 01-11 [Z-terL-butyl peroxy-(3 phenyl) propylidene- 2-peroxy] 1,3 diisopropylbenzene;

26) a-a [1-cumyl-peroxy-(4-tert.-butyl) cyclohexylidene-l-peroxy] 1,3 diisopropylbenzene.

Both the hydroxyl diperoxides and the tetraperoxides obtained according to this invention are soluble in aliphatic and aromatic hydrocarbons, chlorinated aliphatic and aromatic solvents, aliphatic alcohols, and aliphatic esters.

According to another and particularly interesting aspect of this invention, it has been found that the peroxides of this invention act as excellent vulcanizing agents for saturated elastomers, crosslinking agents for plastomers, and as initiators for radical polymerizations.

vulcanization of the ethylene-propylene copolymer is carried out at a temperature comprised between about 140 and 190C, preferably between about 150 and 180C, for periods of from about to 200 minutes, preferably between about 5 and minutes.

The concentration by weight of the peroxide should be between about 0.5 and 10 percent, preferably between about 2 and 5 percent, based on the elastomer.

A particularly suitable vulcanization recipe is the following:

ethylene/propylene copolymer 100 parts carbon black -80 parts ZnO 1-10 parts sulfur 0.15-0.5 parts peroxide 0.005-0.02 parts The use of the peroxides of the invention as crosslinking agents for plastomers finds specific application for polyolefins, particularly polyethylene, inasmuch as its mechanical resistance at high temperatures is improved, its brittleness at low temperatures is decreased, and its solubility in aliphatic hydrocarbons, aromatic hydrocarbons, and chlorinated hydrocarbons is decreased. Moreover, the resistance of the polymer to light, to weather and to aging is improved.

The crosslinking is carried out at a temperature comprised between about 100 and 200C, preferably between about 145 and 165C, at a pressure between about 50-200 kg/cm for a period of time of from about 5 to 60 minutes, preferably from about 10 to 30 minutes.

The concentration by weight of the peroxide is between about 0.5 and 10 percent, preferably between about 2 and 5 percent, based on the plastomer.

The most significant advantages offered by the use of the peroxides according to this invention in the vulcanization of saturated elastomers and in the crosslinking of plastomers, are:

1. The capability of obtaining virtually odorless vulcanized and crosslinked products;

2. Absence of blooming phenomena;

3. Short vulcanization times and low vulcanization temperatures;

4. Improved effectiveness remains unchanged even in the presence of conventional additives such as fillers, reinforcing agents, additives, co-agents, plasticizers, pigments and anti-oxidants. The following examples further illustrate the invention. All parts are by weight unless otherwise stated.

EXAMPLE 1 200 cc of ethyl ether, 60.6 g of 1.3-diisopropylbenzenebis-hydroperoxide-sodium salt at 67 percent, 51 g of cyclopentanone at 99 percent and 20 g of ground anhydrous calcium chloride, were introduced into a flask provided with a stirrer.

This mixture was cooled down to from -l5 10C and over a 20 minute period there were slowly introduced 60 g of HCl at 36 percent. The mixture was then stirred for 1 hour at 5C. The ether solution was then washed with water and treated with anhydrous sodium sulfate.

The a-a'( l-hydroxy-cyclo pentylidene-1-peroxy)l ,3 diisopropylbenzene thus obtained (53 g determined analytically) showed the following characteristics:

lodometric titre 98% Half life 30 minutes at 98C Decomposition temperature 45C C found 66.40 (calculated 66.98) H found 8.2 (calculated 8.69)

ln a 10% toluene solution after'80 hrs. at40C no degradation occurred.

EXAMPLE 2 53 g 'of a oi"(1hydrdxy-cyclopentylidene-1peroxy)1,3 diisopropylbenzene obtained according to Example 1 and dissolved in 200 cc of ethyl ether, 44 g of tert.buty1 hydroperoxide at percent, and 40 .g of ground anhydrous calcium chloride, were introduced into a flask provided with a stirrer.

The ether solution was then cooled down to -10C and over a 5 rn'iriute period there were introduced 20 g of hydrochloric-acid at 36 percent. The temperature was permitted to rise to 0C and the solution was stirred for 1 hour at 0C.

The ether phase was then washed, first with water, then with NaOH at 5 percent, andthen again with water. The solvent was then removed under vacuum at 30C, thereby obtaining 69 g of product, namely, aa'( l-tert.butyl peroxy-cyclopentylidene-l-peroxy)1,3 diisopropylbenzene.

The product? thus obtained showed the following characteristics:

' lodometric titre: 99%

Decomposition temperature: 114C Half life at 123C: 30 minutes C%: found 66.5 (calculated 66.88) 11%: found 9.4 (calculated 9.36)

EXAMPLE 3 7 36 percent. The temperature was maintained at C and the mixture was kept under stirring for 1 hour.

The ether solution was then washed with water and then concentrated under vacuum, avoiding completely evaporation of the ether.

The a-a'( 1-hydroxy-4-tert.-butyl-cyclohexylidene-l peroxy)l ,4-diisopropylbenzene thus obtained (66 g determined analytically) was kept in solution so as to be ready for subsequent reaction, and showed the following characteristics;

lodometric titre 98.5% Decomposition temperature 62C Half-life at 112C 30 minutes C found 70.4 (calculated 71.87) H found 10.1 (calculated 10.18)

EXAMPLE 4 150 g of ether solution containing 66 g of a-a'(1- hydroxy-4-tert.-butyl-cyclohexylidene-l-peroxy)1,4- diisopropylbenzene obtained according to Example 3, 44g of tert.buty1 hydroperoxide at 80 percent, and 42 g of ground anhydrous calcium chloride were introduced into a flask provided with a stirrer.

The solution was then cooled down to -5C and over a 5 minute period there were introduced 30 g of HCl at 36 percent. Care being taken not to exceed 0C, the solution was then left under stirring at this temperature for 1 hour. The ether phase was washed with water, then with NaOH at 5 percent, and then again with water.

The solvent was subsequently removed under vacuum at 30C, thereby obtaining a residue (76 g) identified as a-a'( 1-tert.-butyl-peroxy-4-tert.-butylcyclohexylidene- 1 -peroxy) 1,4 diisopropylbenzene and having the following characteristics:

Melting point 3234C lodometric titre 99.8% Decomposition temperature 109C Half life at 121C 30 minutes C found 69.6 (calculated 70.75) H found 10.5 (calculated 10.40)

EXAMPLE 5 200 cc of benzene, 81 g of 1,3-diisopropylbenzenebis-hydroperoxide-sodium salt at 67 percent, 33.5 g of cyclohexanone at 99 percent, and 25 g of ground anhydrous calcium chloride were introduced into a flask provided with a stirrer.

The mixture was then cooled down to -C and over a period of 30 minutes there were slowly introduced 80 g of HCl at 36 percent. The mixture was then left under stirring for 1 hour at -5C.

The benzene solution was then washed with water and therafter was dehydrated with anhydrous sodium sulfate.

The a-a( 1-hydroxy-cyclohexylidene-1-peroxy)1,3- diisopropylbenzene thus obtained (71 g determined analytically) was maintained in solution. This product showed the following characteristics:

lodometric titre: 98% Decomposition temperature: 55C Half-life at l C 30 minutes C found 68.0 (calculated 68.22) H found 9.0 (calculated 9.07)

EXAMPLE 6 Into a flask fitted with a stirrer was introduced 71 g of a-a(1-hydroxy-cyclohexylidene-l-peroxy)1,3-diisopropylbenzene dissolved in 200 cc of benzene (obtained according to Example 5), 59 g of tert.-butyl hydroperoxide at percent, and 45 g of ground anhydrous calcium chloride.

The benzene solution was cooled. down to --10C and over a 5 minute period there were introduced 27 g of hydrochloric acid at 36 percent. The solution was then left under stirring for 1 hour at 5/0C. The organic phase was then washed, first with water, then with NaOH at 5 percent, and then again with water.

The benzene solution was then filtered on a layer of anhydrous sodium sulphate and celite and the solvent was removed under vacuum at 30C.

Therebywere obtained 91 g of a product identified as a-a'( 1-tert.-butyl-peroxy-cyclohexylidene-l peroxy)1,3-diisopropylbenzene. The product showed the following characteristics:

lodometric titre: 98.5% Decomposition temperature: 1 13C Half-life at C 31 minutes C found 67.5 (calculated 67.81) H found 9.6 (calculated 9.6

EXAMPLE 7 Into a flask provided with a stirrer were introduced 200 cc of benzene, 50 g of 1,3-diisopropylbenzene-bishydroperoxide (sodium salt) at 60 percent, 15.8 g of methylethylketone, and 30 g of ground anhydrous calcium chloride. The mixture was cooled down to -5 to 0C and over a 30 minute periodthere were then slowly introduced 49 g of HCl at 36 percent. The mixture was then stirred for 1 hour at 0C. The benzene solution was washed with water and then dehydrated with anhydrous sodium sulfate.

The a-a'(2-hydroxy-n-butyliden-2 peroxy)1,3-diisopropylbenzene thus obtained (37 g determined analytically) showed the following characteristics:

lodometric titre: 97% Decomposition temperature: 50C Half-life at 122C 30 minutes C found 65.3 (calculated 64.84) H found 9.1 (calculated 9.25)

EXAMPLE 8 Into a flask provided with a stirrer were introduced 37 g of a-a'(2-hydroxy-n-butyliden-2-peroxy)l ,3- diisopropylbenzene (obtained according to Example 7), dissolved in 200 cc of benzene, 40 g of tert.-butyl hydroperoxide at 75 percent, and 40 g of ground calcium chloride. The benzene solution was then cooled down to 5C and over a 10 minute period there were introduced 30 g of hydrochloric acid at 36 percent. The temperature was allowedto rise to +5C and the solution was stirred for 1 hour at this temperature. The benzene phase was then washed with water, then with NaOH at 5 percent, and again with water.

The solvent was then removed under vacuum at 30C, thereby obtaining 39.5 g of a slightly straw-colored liquid residue identified as a-a'(2 tert.-butylteristics:

n 1.437 v lodometric titre: 94.6% Decomposition Temperature: t 105C Half-life at 1 14C 30 minutes c found 65.8 (calculated 65.34) H found 9.7 (calculated 9.75.

EXAMPLE 9 Into a flask provided with a stirrer were introduced 100 cc of benzene, 100 g of 1,3-diisopropylbenzenebis-hydroperoxide (sodium salt) at 60%, 81 g of 2,6,8 trlmethyl-4-nonanone and 30 g of ground anhydrous calcium chloride. The mixture was then cooled down to 5C to C, and over a 30 minute period there were introduced 95 g of hydrochloric acid at 36 percent. The temperature rose to +C and the mixture was then left under stirring for 1 hour. The benzene phase was then washed with water and then treated with anhydrous sodium sulfate.

The a-a'(4-hydroxy-2,6,8 trimethyl-nonylidene-4- peroxy) 1,3-diisoprophylbenzene thus obtained (115 g determined analytically) showed the following charac- 94% 67C 30 minutes lodometric titre:

Decomposition temperature:

Half-life at 107C C found 71.7 (calculated 72.68) H found 10.9 (calculated 11.18)

EXAMPLE 1 g of 04-01 (4-hydroxy-2,6,8-trimethyl-nonylidene- 4 peroxy) 1,3-diisopropylbenzene (obtained according to Example 9) dissolved in 100 cc of benzene, 79.5 g of tert. butyl hydroperoxide at 75 percent, and 40 g of ground anhydrous calcium chloride were introduced into a flask provided with a stirrer.

The solution was then cooled down to 5C and over 9 10 minute period there were introduced 40 g of hydrochloric acid at 36 percent. Due to the exotherm, the temperature rose to +5C and the solution was then left under stirring at +5C for 1 hour. t

The benzene phase was washed with water, then wit NaOH at 5 percent, and again with water. The solvent was then removed under vacuum at 30C, thereby obtaining a liquid residue of a slight brownish color which a-a'(4-tert.-butyl-peroxy-2,6,8-

was identified as trimethyl-nonylidene-4-peroxy)1 ,3-diisopropylbenzene, which product has the following characteristics:

n,'," 1.4576 lodometric titre: 1 92% v Decomposition temperature: 109C Half-life at 116C 7 I 30 minutes C found 71.3 (calculated 71.50) H found 11.1 (calculated 11.18)

EXAMPLE. 11

The mixture was then cooled down to -l0C and over a 25 minute period there were introduced g of hydrochloric acid'at 36 percent. 'The mixture was "stirred for 1 hour at +5C. The benzene solution was then washed-with waterand thereafter wasdehydrated with anhydrous sodium sulfate.

The oz-ot'(1-hydroxy-cyclododecylidene-l perox- 'y)'l,4-diisopropylbenzene thus obtained g determined analytically) showed the following characteristics:

lodometric titre:

p 98% Decomposition"temperature: 59C Half-life at 114C:

a 30 minutes C found 73.3 (calculated 73.17) 1-1 found 10.3 (calculated 10.58)

' anhydrous calcium chloride. The benzene solution was then cooled down to 0C and over a 10 minute period there were introduced 5 g of hydrochloric acid at 36 percent.

The temperature was then allowed to rise to +5C and the solution was then stirred for 1 hour at this temperature (+5C). The benzene phase was then washed with water, with NaOh at 5 percent, and then again with water.

The solvent was then removed under vacuum at 40C, thereby obtaining 48 g of a yellow liquid residue identified as a-a'(l-tert.-butyl-peroxy-cyclododecylidene-l peroxy 1,4-diisopropylbenzene. The product showed the following characteristics:

c found 70.2 (calculated71.89) H found 10.9 (calculated 10.7)

EXAMPLE 13 7 into a flask provided with a stirrer, were introduced 50 cc of benzene, 50 cc of ethyl ether, 60.6 g of 1.3- diisopropyl-benzene-bis-hydroperoxide (sodium salt) at 67 percent, 27.7 g of benzyl-methyl-ketone at 97 percent, and 30 g of ground anhydrous calcium chloride. This mixture was then cooled down to 15C and then were slowly added, over a 30 minute period, 60 g of HCl at 36 percent. Thereafter the mixture-was kept under stirring for 1 hour at -5C.

The organic solution thus obtained was then washed with water and then was dehydrated with anhydrous sodium sulfate. The product thus obtained (37 g determined analytically identified as a-a'[2-hydroxy-(3- phenyl) propylidene-2 peroxy] 1,3-diispropylbenzene,

was kept in solution.

An isolated analytical sample showed the following 0% found 719% (calculated 72.85) H %:-'found 734% (calculated 7.74)

EXAMPLE 14 Into a flask provided with a stirrer were introduced 37 g of a -a'[2-hydroxy-(3-phenyl)propylidene-Z peroxy]1,3 diisopropylbenzene (obtained according to Example 13) dissolved in 50 cc of benzene and 50 cc of ether, 45 .2 g of tert.-butyl hydroperoxide at 80 percent, and 20 g ground anhydrous calcium chloride. This solution was then cooled down to C and in over a minute period there were added 20 g of hydrochloric acid at 36 percent.

The exotherm caused the temperature to rise to +5C and the solution was maintained at this temperature for one hour under stirring Thereafter the organic phase was washed with water, with NaOH at 5 percent, and again with water until neutrality.

Then the solvent was removed under vacuum at 50C, thereby obtaining a slightly opalescent liquid residue (44 g), identified as a-a'[2-tert.-butyl-peroxy- (3-phenyl)propylidene-2 peroxy] 1,3-diisopropylbenzene, having the following characteristics:

lodometric titration: 75% Decomposition temperature: 132C Half-life at 123C: 30 minutes C found 72.9% (calculated 71.44) H found 8.5% (calculated 8.52)

EXAMPLE Into a flask provided with a stirrer were introduced 50 cc of benzene, 50 cc of ethyl ether, 21.4 g of 1,3diisopropylbenzene-bis-hydroperoxide (sodium salt) at 67 percent, 19.3 g of 4-tert.-butyl-cyclohexanone, and 10 g of ground anhydrous calcium chloride. This mixture was then cooled down and over a minute period there were introduced dropwise 20 g of HCI at 36 percent. The mixture was then subjected to stirring for 1 hour at 5C.

The organic solution was washed with water and was then dehydrated with anhydrous sodium sulfate. The residue (32 g determined by analysis), identified as a-a'[ 1 -hydroxy-( 4-tert.-butyl)-cyclohexylidene-1 peroxy]1,3-diisopropylbenzene, was kept in a solution. An analytical isolated sample showed the following characteristics:

lodometric titre: 95% Decomposition temperature: 78C Half-life at l 10C 30 minutes C found 71.3% (calculated 71.87) H found 10.0% (calculated 10.18)

EXAMPLE l6 Into a flask provided with a stirrer were introduced 32 g of a-a'[1-hydroxy-(4-tert.-butyl)cyclohexylidene- 1 peroxy] 1,3-diisopropylbenzene, dissolved in 50 cc of benzene and 50 cc of ether, and 15 g of anhydrous calcium chloride. Over a period of 20 minutes there were then introduced into the mixture, at a temperature of-l 5C, 43.9 g of cumene hydroperoxide at 83.4 percent. The solution was cooled down again to 15C, and there were introduced 10 g of HCl at 36 percent over a 10 minute period. The exotherm caused the temperature to rise to 5C and the solution was then left under stirring for one hour at between 5 and 0C.

The organic phase was washed with water, with NaOH at 5 percent, and then again with water until reaching neutrality. The solvent was then removed under vacuum at 50C, thereby obtaining a slightly oily residue, identified as an a-a'[l cumyl-peroxy(tert.- butyl)cyclohexylidene-1 peroxy]1,3-diisopropylbenzene, and it showed the following characteristics:

lodometric titre: Decomposition temperature: 114C Half-life at 125C: 30 minutes C found 75.1% (calculated 74.4) H 7:: found 8.5% (calculated 8.52)

EXAMPLE 17 200 cc of n-hexane, 50 g of 1,3-diisopropylbenzenebis-hydroperoxide-sodium salt at 60 percent, 29 g of acetoacetic acid ethyl ester at 99 percent and 30 g of ground anhydrous calcium chloride were introduced into a flask provided with a stirrer. The mixture was then cooled down to 10-5C and over a period of 30 minutes there were introduced 45 g of HCl at 36 percent. The mixture was then left under stirring for 1 hour at 5C. The organic phase was then washed with water and thereafter was dehydrated with anhydrous sodium sulfate. The a-a[2-hydroxy-(3 ethoxy-carbonyl)-isopropylidene-2 peroxy] 1,3-diisopropylbenzene thus obtained (43 g determined analytically) showed the following characteristics:

lodometric titre Decomposition temperature 47C Half-life at 1 18C 30 minutes C found 60.1 (calculated 59.24) H found 7.65 (calculated 7.87)

EXAMPLE l8 Into a flask fitted with a stirrer were introduced 43 g of a-a[2-hydroxy-(3 ethoxy-carbonyl)-isopropylidene -2 peroxy] 1,3-diisopropylbenzene (obtained according to example 17) dissolved in 200 cc of n-hexane, 40 g of tert.-butyl hydroperoxide at 75 percent and 40 got ground anhydrous calcium chloride. The solution was cooled down to 10C and over a 10 minute period there were introduced 30 g of HCl at 36 percent. The temperature was allowed to rise to 0C, and the solution was stirred for 1 hour at this temperature. The organic phase was then washed with water, then with NaOH at 5 percent and then again with water. The solvent was removed under vacuum care being taken not toexceed 30C, thereby obtaining 47 g of slightly yellow-coloured viscous residue identified as a'a'[2- tert.-butyl-peroxy-(3 ethoxy-carbonyl) isopropylidene- 2 peroxy] 1,3-diisopropylbenzene. This product showed the following characteristics:

, 0.937 n 1.489 lodometric titre 97 Decomposition temperature 109C Half-life at 118C 30 minutes C found 61.4 (calculated 60.93) H-%: found 8.63 (calculated 8.63)

EXAMPLE 19 Into a flask provided with a stirrer were introduced 150 cc of benzene, 23.5 g of 1,4 diisopropylbezene-bis- EXAMPLE 21 Vulcanization Vulcanization tests were carried out on mixes of an hydroperoxide at 97,3 percent, 18 g of acetoacetic acid e-thylehe propy!ene copolymer having a molar ratio ethylester at 99 percent and g of anhydrous calclum ethylene/propylene 50/50 and a viscosity Mooney ML ch1or1de.The m1xture was then cooled down to 10C u 4) 1000C: 3 In Table 1 there were compared the i f ls there were g i g vulcanization rates determined on the same mixes o a percent. e m1xture was t en stirre at 1 a this temperature for 1 hour. The benzene phase was 10 contammg as peroxldes respectively washed with water and then treated with anhydrous 1 l-t L- lsodium sulfate. The a-a'[2-hydroxy-(3-ethoxycarboa l ;g g:; gi;: l peroxy) nyl) lsoprppyhdenea qi dusoliropylbenzene a-a"(1-tert.-butyl-peroxy- 4tert.-butyl-cyclohexylidenethus obtained (29 g ana11t1ca11y determmed) showed l peroxy) l 4 diisopropylbenzene I 15 the following charactensucs' a-a'( l-tert.-b1.ityl-peroxy cyclohexylidenel -peroxy) 1,3 diisopropylbenzene;

lgggfigg ga 2%,? a'[2-ter.-buty1 peroxy (3-ethoxycarbonyl) isopropyli- Half-life at 115C 30 minutes dame-2 P y] p py n C found 58.6 (calculated 59.24) dicumyl roxid H found (calculated 7'87) The vulcanization rate was determined at 177C on a Monsanto TM-lO rheometer. The mixes used in the EXAMPLE 20 test were of the followmg compos1t1on:

150 cc of benzene containing 29 g of a-a'[2-hydroxy h l i -j p l copolymer 100 parts (3-ethoxycarbonyl) isopropyl1dene-2-peroxy]-1,4 carbon black 50 parts diisopropylbenzene (obtained according to example 1 3:3:

19) and 15 g of anhydrous calcium chloride were intro- .peroxide 0.01 mol duced into a flask fitted with a stirrer. Over a 20 minute i C there were4mtmduce%:3'9 g of 30 Table 2 reports the physical characteristics of vulcacumy r9peroxlde percent e lemperatllre nized products obtained by using as peroxides, respecwas mamtamed to 15 C and over a 10 m1nute per1od tively v there were introduced 10 g of l-lCl at 36 percent. Due to the exotherm the temperature rose to -5 C and at i t 1- r xy-cyclopentylidene-l-peroxy) th1s temperature the solution was then left under stirl 3 diiso lb propy enzene, ring for 1 hour. The orgamc phase was then washed a1(1 tert butyl peroxy 4 tert butyl cyclohexy|i w1th water, then w1th NaOH at 5 percent and again deneJmGmXy) 1 4 diisopropylbenzene, with water until neutrality. The solvent was removed a,(14ert guyi?proxy cyclohexilidenejl138m) under vacuum at 30C thereby obtaining 38 g of a 1 3 diisopropylbenzene slighty oily straw-colored residue identified as a-a'[2- 40 1 cumyl'pemxy..(3 'ethoxy carbonyl). lsoprpyhden.e'2 for vulcanization: times comprised between 5 and peroxyll 4 d11sopropy1benzene having the followmg minutes at C in comparison with the physical charactensncs: properties of th zyulcanized products obtained by using dicumyl peroxide and operating at C for a vu1cani- {'gSlT 45 zation time of 30 minutes (these being the optimal Decomposition temperature 121C conditions for l Peroxide) Halt-life at 122C 30 minutes From the results reported in Table 2, it 1s qu1te evi- E ZZ' 3g; 223 dent that at low temperatures high vulcanization rates and better phys cal charactenstics of the vulcamzed 50 product are obtained with the peroxides of the invention as contrasted to the use of dicumyl peroxide. TABLE 1 vulcanization Rate I Peroxide Vulcanization v p y at the RHEOMETER TYPE Parts per 1010. of Vulcanization vulcanization ethylenelpropy ene temperature time copolymer "C minutes g moles CH l 3 (CH l COO OOC I COQ OOClCH l CH CH vulcanization Rate Peroxide vulcanization at the RHEOMETER TYPE Parts per 100 of vulcanization vulcanization ethylene/propy ene temperature time copolymer C minutes g moles i"= a": lcu l coo oo$ loo comm 6.79 4.5

cm cu cu -c-cH cu C-CH a a a cw cu e i" (cn coo o? c|oo oocmn l 5.66 6

CH3 cw a-a'[2-ter.-butylperoxy(3-ethoxycarbonyl) isopropylidene-Z peroxy]l.3 diisopropylbenzene 6,3 7 Dicumylperoxide 2 7() 14 TABLE 2 Physical Characteristics of the Vulcanized Product Peroxide vulcanization Parts per [00 of Temperature Time ethylene/propy ene C minute copolymer moles g I 150 in in (ca 1 coo ooc -coo OOClcl-l 0.01 5.38 a a I a 3 ca 3 c H 3 i: H' 5 (CH cOO ooc-@coo ctcu 0.01 6.79 I, 10 I 15 cu cu 30 Y! cu I-CM cn -c -cu ca 3 cu cu CH 3 3 1 5 0 5 lCH COO ooc ioo ooclcu O 01 5 5 H ca 3 CH 3 30 I! Dicumylperoxide 0.01 2.70 30 Physical properties of the vulcanized product Tensile Elongation Modulus Modulus Modulus I.R.H.D. strength, at break, at 100% at 200% at 300% hardness kg/cm kg/cm kg/cm kg/cm TABLE 2-continued 1 Physical Characteristics of the Vulcanized Product T Peroxide ,7 I v vulcanization Parts per 100 of Temperature Time ethylene] ropy ene C minute copo ymer moles g 198 420 23 61 1'19 67 l86 380 25 68 130 67 l 350 78 155 68-69 203 340 27 81 164 69 202 850 26 75 158 69 190 330 28 84 l68 69 178 340 25 72 I48 69 199 490 22 54 I03 66 I95 460 23 53 104 67 203 440 24 56 1 l0 67-68 202 410 25 63 I26 68 I88 400 24 57 123 68 I80 410 21 58 l 19 68 lidenel erox l 4 diiso r0 lbenzene and the On a mix having the following composition:

ethylene/propylene copolymer 100 parts carbon black 50 parts ZnO 3 parts sulfur 0.32 a-a'[2-tert.-butyl eroxy (3-ethoxycarbony isopropylidene-Z peroxy] 1,3 diisopropylbenzene 0.01 mol known peroxide (dicurnylpjroxide).

EXAMPLE 24 I swelling?v is nieant'the volume of solvent absorbed by was carried out the vulcanization test at 150C for 15 minutes. The vulcanized product showed the following physical characteristics:

Tensile strength (kg/cm) 185 Elongation at break 412 Modulus at 200% (kg/cm) 6l Modulus at 300% (kg/cm) 108 l.R.H.D. hardness 67-68 EXAMPLE 23 Crosslinking unit of volume of crosslinked polyethylene.

' The method consists in suspending a small basket or cage containing a crosslinked polyethylene plate of about 0.2 g in a test tube containing 100 cc of xylene stabilized with 0.1 g of the phenolic antioxidant 4,4-

wherein:

a weight of the test sample after 21 hours at C in xylene, b weight of the test sample before the test, 0 weight of the test sample after drying at the end of the test.

density of polyethylene'at 80C V "density of xylene atfl80C The obtained results, compared with those in which dicumylperoxidewas used, are listed in Table 4.

TABLE 3 'Crosslinking of low-density (0.918 polyethylene I Physical characteristics.

Moles of Crosslinking Yield Tensile Elonga- PEROXIDE Peroxide Ti rne Temper. point strength tion in g mrns. C kg/cm' kglcm at break vofpolyethylene None L 20" 57.8 73 1 TABLE 3-continued Crosslinking of low-density (0.9181 polyethylene Physical characteristics.

Moles of Crosslinking Yield Tensile Elonga- PEROXIDE Peroxide Time Temper. point strength tion in 100 g mins. C kg/cm kg/cm at break of poly ethylene 1" (01 l coo ooc-Qgoo c101 0.01 20 145 52.7 137 260 CH3- e-oni (H -c 491 cu 3 ca 3 Dicumylperoxide 0.01 20 14's 52.9 132 456 TABLE 4 Crosslinking of low-density (0.918) polyethylene Degree of swelling.

Moles of Crosslinking Degree of PEROXIDE Peroxide Time Temper. swelling in 100 g minutes C of polyethylene n in 1 (cm coo 00% Too 006104 1 0.01 20 145 16.5

c a ,c

c I Q 3 (1214 1 600 out-@(oo (M14 1 0.01 20 1 145 20.2

CN H3 CH3 N3 -CM CH3 zujfl CH3 E": 3

Dicumylperoxide 0.01 20 145 21.3

Variations can, of course, be made without departing 4. 02-01 (l-cumyl peroxy-cyclopentylidene- 1 -peroxy) from the spirit and scope of the invention. 1.4 diisopropylbenzene;

Having thus described our invention, what we desire 5. (1-04 (l-tert.-butyl peroxy-cyclohexylidene-l to secure by Letters Patent and hereby claim is. 60 peroxy) 1,3 diisopropylbenzene;

1. A tetraperoxide selected from the group consisting 6. 01-04 (1-tert.-butyl peroxy-cyclohexylidene-l1 of peroxy) 1,4 diisopropylbenzene;

1. a-a' (1-tert.-butyl peroxy-cyclopentylidene-1- 7. 1-01 (l-cumyl peroxy-cyclohexylidene-l-peroxy) peroxy) 1,3 diisopropylbenzene; 1,3 diisopropylbenzene; 2. 01-01 (1-tert.-butyl peroxy-cyclopentylidene-1- 65 8. (1-01 (l-cumyl peroxy-cyclohexylidene-l-peroxy) peroxy) 1,4 diisopropylbenzene; 1,4 diisopropylbenzene; 3. 01-01 (l-cumyl peroxy-cyclopentylidene-1-peroxy) 9. 01-0 (1-tert.-butyl peroxy-4 tert.-'butyl-cyclohex- 1,3 diisopropylbenzene; ylidene-l-peroxy) 1,3 diisopropylbenzene;

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent; No, Dated December 23,

Inventofls). EGEO SACRINI and CLAUDIO CAVALLOTTI Pa '1 f 3 It: is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Title page, right side, the formula:

R. I R,-OO--( .'OO--XOOZ--R Should l a read m-oo-dwo-x-oo-(E-oo-n. R: R, i. 1|:

Column 2, line 49: "from" should read form Column 3, lines 32-33: "0) oa-on' (4-hydroXy-2, 6,8 trimethyl nonylidene-h-peroxy) 1,3 diisopropylbenezene;" should read cz-oa' (4-hydroXy-2, 6,8 trimethyl nonylidene-4-per0xy) 1,3 diisopropylbenzene; line 50: "2,5-dimethyl-2,5-

dihydroperoxide-hexene-3;" should read 2,5-dimethyl2,5-

dihydroperoxide-heXane-3;

Column 4, line 2: "methane" should read menthane line 6: "cycloalkphatic" should read cycloaliphatic line 16: ."take" should read takes Column 8, line 6: '59 g." should read 58 g.

a Column 9, line 9: (calculated 9.75. should read (calculated 9.79) line 45: "9 10 minute" should read a 10 minute v a UNITED STATES PATENT OFFICE. CERTIFICATE OF CORRECTION Patent No. 3,928,467 Dated December 23, 1975 G I EGEO SACRINI and 0111101310 CAVALLOTTI Page 2 f 3 p It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 10, line 32: "NaOh" should read NaOH line 47: "into" should read Into Column 11, line 24: "1,4988" should read 1.4988

Column 12, line 11; "1,4985" should read 1.4985

Column 13, lines 4-5: "1,4 diisopropylbezene-bis-hydroperoxide at 97,3 percent," should read 1,4 diisopropylbenzene-bis-hydroperoxide at 9-7.3 percent, line 30: "83,4" should read 83 .4 lines 47-48: "65,3" and "7,32" should read 65.3 and 7.32

Column 14, line 8: "100C 3, should read 100C G 35. lines 18-19: "01' [2-ter.butyl peroxy (3-ethoxycarbonyl) isopropylidene-Z peroxy] 1,3 diisopropylbenzene;" should read 01-01' [2-ter.-butyl peroxy (3-ethoxycarbonyl) isopropylidene-Z peroxy] 1,3 diisopropylbenzene;

Q Columns 15-16, column 1 of Table 1, first formula:

n m CH should "1 ,J

I 3 1 3 read (01 1 :00 00' E00 ooclcn lcu l coo OOi-OfiOO 006(c)(3):

CH] CH] v I ("j-E-CH] CNy-g-CNJ CH --(-CH CH c (H CH1 Columns 17-18, the heading of Table 2-continued:

w UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 i 928 7 Dated December 23 1975 Inventor(s)EGEO SACRINI and CLAUDIO CAVALLOTTI Page 3 of 3 It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

" TABLE 2-continued n Physical Characteristics of the Vulcanized Product Peroxide vulcanization- Parts per 100 of Temperature Time cthylcnc/ vropy ene C minule copo ymcr moles g should read Physical properties of the vulcanized product Tensile Elongation Modulus Modulus Modulus l.R.H.D. strength, at break, at l00% at 200% at 300% hardness kg/cm kg/cm" kg/cm ltglcm Columns 17-18, column 2 of Table 2: "850" should read Columns 19-20, column 1, formula of Table 3:

cu c lcn l coo ooclcoo ctcu Should read c u cu t -c-cu cu -cu ca 3 cu i": 5" tcu l coo ooc coo CKCMJLJ en en ca e-ca (HJ-C-CH] a Signed and Scaled [Sm] Fifth Day of October 1976 A nest:

RUTH C. MASON Arresting Officer C. MARSHALL DANN Commissioner of Parents and Trademarks 

1. A TETRAPEROXIDE SELECTED FROM THE GROUP CONSISTING OF
 1. A-A'' (1-TERT.-BUTYL PEROXY-CYCLOPENTYLIDENE-1-PEROXY) 1,3 DIISOPROPYLBENZENE;
 2. A-A'' (1-TERT.-BUTYL PEROXY-CYCLOPENTYLIDENE-1-PEROXY) 1,4 DIISOPROPYLBENZENE;
 2. Alpha - Alpha '' (1-tert.-butyl peroxy-cyclopentylidene-1-peroxy) 1,4 diisopropylbenzene;
 3. A-A'' (1-CUMYL PEROXY-CYCLOPENTYLIDENE-1-PEROXY) 1,3 DIISOPROPYLBENZENE;
 3. Alpha - Alpha '' (1-cumyl peroxy-cyclopentylidene-1-peroxy) 1,3 diisopropylbenzene;
 4. Alpha - Alpha '' (1-cumyl peroxy-cyclopentylidene-1-peroxy) 1,4 diisopropylbenzene;
 4. A-A'' (1-CUMYL PEROXY-CYCLOPENTYLIDENE-1-PEROXY) 1,4 DIISOPROPYLBENZENE;
 5. A-A'' (1-TERT.-BUTYL PEROXY-CYCLOHEXYLIDENE-1-PEROXY) 1,3 DIISOPROPYLBENZENE;
 5. Alpha - Alpha '' (1-tert.-butyl peroxy-cyclohexylidene-1-peroxy) 1,3 diisopropylbenzene;
 6. Alpha - Alpha '' (1-tert.-butyl peroxy-cyclohexylidene-1-peroxy) 1,4 diisopropylbenzene;
 6. A-A'' (1-TERT.-BUTYL PEROXY-CYCLOHEXYLIDENE-1-PEROXY) 1,3 DIISOPROPYLBENZENE;
 7. A-A'' (1-CUMYL PEROXY-CYCLOHEXYLIDENE-1-PEROXY) 1,3 DIISOPROPYLBENZENE;
 7. Alpha - Alpha '' (1-cumyl peroxy-cyclohexylidene-1-peroxy) 1, 3 diisopropylbenzene;
 8. Alpha - Alpha '' (1-cumyl peroxy-cyclohexylidene-1-peroxy) 1, 4 diisopropylbenzene;
 8. A-A'' (1-CUMYL PEROXY-CYCLOHEXYLIDENE-1-PEROXY) 1,4 DIISOPROPYLBENZENE;
 9. A-A'' (1-TERT-BUTYL PEROXY-4 TERT.-BUTYL-CYCLOHEXYLIDENE1-PEROXY) 1,3 DIISOPROPYLBENZENE;
 9. Alpha - Alpha '' (1-tert.-butyl peroxy-4 tert.-butyl-cyclohexylidene-1-peroxy) 1,3 diisopropylbenzene;
 10. A-A'' (1-TERT-BUTYL PEROXY-4 TERT. BUTYL-CYCLOHEXYLIDENE 1-PEROXY) 1,4 DIISOPROPYLBENZENE,
 10. Alpha - Alpha '' (1-tert.-butyl peroxy-4 tert.-butyl-cyclohexylidene-1-peroxy) 1,4 diisopropylbenzene;
 11. A-A'' (1-TERT.-BUTYL PEROXY-CYCLODODECYLIDENE-1-PEROXY) 1,3 DIISOPROPYLBENZENE;
 11. Alpha - Alpha '' (1-tert.-butyl peroxy-cyclododecylidene-1-peroxy) 1,3 diisopropylbenzene;
 12. Alpha - Alpha '' (1-tert.-butyl peroxy-cyclododecylidene-1-peroxy) 1,4 diisopropylbenzene;
 12. A-A'' (1-TERT.-BUTYL PEROXY-CYCLODODECYLIDENE-1-PEROXY) 1,4 DIISOPROPYLBENZENE;
 13. A-A'' (1-CUMYL-PEROXY-(4-TERT.-BUTYL) CYCLOHHEXYLIDENE1-PEROXY) 1,3 DIISOPROPYLBENZENE.
 13. Alpha - Alpha '' (1-cumyl-peroxy-(4-tert.-butyl) cyclohexylidene-1-peroxy) 1,3 diisopropylbenzene. 